Rice the source of alcohol flush reaction in Asians? New studies tell us where Asian Flush comes from

If you’re one of the roughly 50% of Asians suffering from Alcohol flush (or one of the many non-Asians suffering from flushing after drinking alcohol), then you’re aware of the embarrassing toll it can take on your social life. You may have even wondered why some people seem to be effected so badly by flushing while others seem to be able to keep drinking without any real side-effects except a bad hangover and some embarrassing dance moves.

Well, new scientific research has emerged showing that a simple dietary staple may be to blame for your annoying flush reaction. This same research might also shed some light on how we might be able to eliminate the symptoms of this condition altogether! Let's dig in...

One solution is to take Alcohol flush pills like Sunset.

The Alcohol Flush Cause

So what is the cause of Alcohol flush? In short, Alcohol flush is a series of effects that result in an inability for some people to properly metabolize alcohol. Follow along with me because some of these words in this section are going to get awful big and medical-sounding.

Acetaldehyde. That’s our first big word. Those five syllables are responsible for Alcohol flush and we've discussed this in-depth previously on the blog.

What is acetaldehyde, exactly, and where does it come from?

 Acetaldehyde is produced as the liver metabolizes alcohol. As the liver enzyme alcohol dehydrogenase breaks down the booze, acetaldehyde is released.

For most people, acetaldehyde is quickly converted into something called acetate. It’s completely harmless and non-toxic. But, for sufferers of Alcohol flush, this process occurs much more slowly, and it results in all of the unpleasant side effects of Alcohol flush.

What Are the Symptoms of Alcohol Flush?

The symptoms of Alcohol flush vary from person to person. Those who suffer from this reaction typically experience things like:

• Redness in the face and upper body
• Swelling of the cheeks
• A warm, tingly sensation
• Racing heartbeat
• Difficulty breathing
• Headache
• Nausea
• Red Eyes
• Dizziness
• A feeling of pressure in the upper body

The More Serious Consequence of Alcohol Flush

Now that we’ve covered the embarrassing-but-not-so-serious side effects of Alcohol flush, there are some more serious matters to discuss as well.

Acetaldehyde is a known carcinogen that has been linked to the development of esophageal cancer. We know that any form of cancer is exceptionally serious, but esophageal cancer is one of the most deadly of all, with five-year survival rates typically below 30%.

Why are some people unable to metabolize alcohol properly?

We can thank the ALDH2 enzyme for that. ALDH2 is the enzyme present in the level that is responsible for converting acetaldehyde into a harmless compound. People who have an alcohol flush reaction inherited from their parents, who inherited the reaction from their parents, and so on.

Why Are Asians Disproportionately Affected by an ALDH2 Deficiency?

It seems strange, doesn’t it? We’ve all been on this earth for thousands of years, and for the most part, all of us have been drinking alcohol. But, Asians seem to be the one group that’s most affected by this phenomenon. Still, we don’t have the answer to the question “why do some people flush following alcohol consumption?”. Fortunately, it seems that science is finally getting down to the bottom of this issue, and it looks like a simple staple food item may be the root cause of Alcohol flush: rice!

Bear with me here: The first instances of flushing in the face as a result of alcohol use were reported around 10,000 years ago. At around the same time was when we first began cultivating rice. Since these timelines seem to match up, the link between rice cultivation and flushing in the face when drinking alcohol is worth investigating.

Bing Su, a geneticist at the Kunming Institute of Zoology in China and a professor at Yale University decided to study the genes of 2275 people from 38 different East-Asian populations, looking for a mutation that modifies the gene that codes for the enzyme alcohol dehydrogenase.

The gene mutation that Su and his team were looking for causes alcohol to be metabolized at 100 times the speed that it otherwise would be. As the enzyme removes alcohol so quickly from the bloodstream, it protects people from the harmful effects of alcohol, and Su believes it confers an evolutionary advantage: a study in the Han Chinese suggests that those carrying the mutation have the lowest risk of alcoholism (American Journal of Human Genetics, vol 65 p 795).

The mutation also causes a by-product of the alcohol’s metabolization to accumulate in the body, which makes those who have the mutation flush red when they drink.

Here’s what Su and his team found in their studies:

• In certain areas of southeast China, nearly all of the subjects of the study suffered from Alcohol flush.
• In areas of western China, about two-thirds to three-quarters of people suffered from this reaction.
• Meanwhile, in northern areas of China where rice cultivation was less prevalent, far fewer people were afflicted.

In more scientific terms, from a scienctic journal summary on Biomedcentral.com:

We studied a total of 38 populations (2,275 individuals) including Han Chinese, Tibetan and other ethnic populations across China. The geographic distribution of the ADH1B*47His allele[editors note: the "class I alcohol dehydrogenase sequence polymorphism (ADH1BArg47His)" mentioned here is another way to say 'enzyme deficiency' at the gene level] in these populations indicates a clear east-to-west cline, and it is dominant in south-eastern populations but rare in Tibetan populations. The molecular dating suggests that the emergence of the ADH1B*47His allele occurred about 10,000~7,000 years ago.

The researchers hypothesize that the cause of this adverse reaction to alcohol is a genetic mutation that was designed to protect early farmers from the potentially fatal effects of alcohol use. At around the exact time that we began cultivating rice, we also realized that rice could be fermented to create an alcoholic drink.

A mutation like this is actually quite common when it comes to human evolution. As humans began incorporating starch into their diets, the enzyme amylase evolved to process it more efficiently. The same goes for the enzyme lactase, which evolved to help us process lactose as we added dairy to our diets (fun fact: more than 65% of the worlds adult population actually suffers from lactose intolerance!).

The idea that this reaction has evolved to protect humans from alcohol use is further supported by the fact that it mirrors many of the symptoms of the drug disulfiram. Disulfiram, sold under the trade name Antabuse, is a drug designed to prevent relapse in alcoholics. If someone taking disulfiram consumes alcohol, they’ll encounter many of the same side effects that they’d experience if they were suffering from flushing from alcohol. Disulfiram actually works by inhibiting acetaldehyde dehydrogenase in the bloodstream, which increases the acetaldehyde in the body by almost tenfold... sound familiar!?

So when it comes to the question of “why am I cursed with this flush reaction after consuming alcohol?” It seems that rice being integrated into our diets thousands of years ago may be to blame!

What can be done about Alcohol Flush? Is there a cure?

Fortunately, if you suffer from this adverse reaction to alcohol, you don’t have to stop imbibing for posterity’s sake, or for health reasons. Thanks to SRQ Labs, a solution has emerged called Sunset Alcohol Flush Support.

The ingredients in Sunset restricts facial histamine reactions (a fancy way of saying you won’t experience flushing in your face) by supporting the ALDH2 enzyme. Most importantly, since Sunset allows the ALDH2 enzyme to function as it normally would, it neutralizes the carcinogenic effects of acetaldehyde.

SRQ Labs have also produces an eBook, called Flushed, that covers dozens of cocktails that have low histamine profiles, and gives plenty of actionable advice on how to reduce flushing whenever you're drinking.